Keys to the Problem Downloaded the "free" ten day trial an am unable to activate. Still am unsure if my computer is safe.

You don't say what product you downloaded that has a free ten day trial. There are a number of good products that are completely free (not just for 10 days). The one I use and like very well is Microsoft Security Essentials:

http://www.microsoft.com/en-us/security_essentials/default.aspx

Make Sure that your System Meets the System Requirements

This error can be due to some configuration requirements for you system. If your computer hardware is not up to par, then make sure you update where necessary before continuing: